Quality Evaluation of Coatings by Automatic Scratch Testing.

摘要

The soundness and comparative quality of various coatings were evaluated with a CSEM-Revetest automatic scratch tester. These coatings were: TiB2 on MP35N alloy, TiN on PH 17-4 steel, on PH 17-4 steel, and plasma-enhanced CVD-processed SiC on 4340 low alloy steel. During scratch testing, the acoustic emission signal intensity, the frictional or tangential force, and the friction coefficient were plotted versus load, as well as time at various constant loads. Scratch test results were correlated with coating microstructure which was investigated by optical and scanning electron microscopy (SEM). Significant difference in quality and soundness was detected for TiN coatings processed by two different methods. This difference was confirmed by abrasive wear resistance measurements. Keywords: Coatings, Ceramic coatings, Adhesion, Acoustic emission, Tribology, Wear resistant coatings. (sdw)